The system of this invention consists of a static microbiological disinfection device by ultraviolet rays, which is permanently assembled at the air inlet or inlets in the duct, so that the micro-organisms contained in the air that is projected inside the circuit by the corresponding ventilation or cooling equipment, are eliminated, plus a mobile microbiological disinfection device by ultraviolet rays, which is placed inside the duct to be cleaned, and which is moved along the length of the duct eliminating any possible micro-organisms which could be inside.
Ventilation and air conditioning ducts are currently cleaned by combining the application of pressurised air on the inside walls with suction from outside the duct; by applying pressurised air, adhered dust particles are separated from the walls, and with suction, these particles are removed from the duct.
Although these mechanical cleaning devices provide good surface cleaning of dust particles and dirt stuck to the duct, they are not sufficient to microbiologically clean. However, it is known that micro-organisms multiply in these ducts, causing many respiratory disorders.
This microbiological cleaning method is attempted by spraying the inside of the duct with disinfectant, that can cause discomfort to certain people, or be harmful to health. Owing to its oxidising power, it can damage the ducts.
To solve these problems, the system that is the purpose of the invention has been designed, aimed at microbiologically cleaning the duct by emitting short-wave ultraviolet rays.
In accordance with the invention, this system is composed of at least one static device which is assembled inside the duct, near the air inlet connected to the corresponding cooling or ventilation equipment.
This static device is composed of a set of short-wave ultraviolet lamps, the purpose of which is to disinfect the air flow entering the duct. It has been planned that these lamps are connected to the corresponding cooling or ventilation equipment, and are kept on while said equipment is operating. This ensures that the incoming air does not contain micro-organisms and is not a continuous source of bacteria, fungus or other simple forms of life inside the duct.
Bearing in mind that these micro-organisms can enter the duct through the ventilation outlets, when there is no forced circulation of air inside, this system is complemented by a mobile device, inserted inside the duct from time to time, and moved inside, thereby fully disinfecting the duct.
According to the invention, this mobile device will be composed of a central axle, around which a series of short-wave ultraviolet ray lamps are assembled, and of two end discs with wheels on the edge forming the support means of the device on the inside surface of the duct.
The lamps of the mobile device are placed parallel to themselves and also to the central axle, emitting ultraviolet radiation which covers an area of 360xc2x0 around the axle.
This mobile device is provided with the corresponding tubing for electric power of the lamps and two resistant cables which are fixed to the opposite ends of the device.
In order to disinfect any part of the duct, the mobile device simply has to be positioned inside, removing the electric input tubing and one of the resistant cables through one of the ventilation openings, and the remaining cable through another of the ventilation outlets.
One of these cables will be used to pull the mobile device causing it to move inside the duct, while the other cable will be used as a retainer, to prevent the device from suddenly accelerating when circulating through a slanted part or through vertical parts of the duct.
In order to fully disinfect the duct by means of the mobile device, the characteristics of the duct should first be observed, such as: type of material of which it is composed, the reflectance index, section, surface roughness, etc.
The radiation applied in each case can be achieved by varying the forward speed of the mobile device, and maintaining the power of the lamps constant, or varying the power of the lamps and maintaining the forward speed of the device constant.
In both cases, in order to set the forward speed of the device, at least one of the cables fixed to the mobile device is adjusted.